That is, a time zone will cover the same countries vertically, which is why the UK and South Africa observe the same time. Once again, this has to do with the rotation of the Earth: noon is noon from North to South, because the poles do not move; West to East, however, sees a difference as the Earth turns around its own axis.
Funnily enough, while time zones are technically strictly defined by geography, it can sometimes be a purely political decision.
For example, India spans a vast territory with several time zones in the geographical sense, but ever since the colonial era, the country observes only one single time zone from border to border. After all, this is precisely what GMT is: an agreement. Introduced to help with naval navigation when travelling around the world, GMT was once the international civil time standard.
GMT was established in the seventeenth century by the Royal Observatory in Greenwich, and it was used by sailors and naval officers as a time reference at different locations around the world.
Remember that whole Earth rotation thing? To account for those missing seconds, the time standard needs to be periodically adjusted to follow the real, atomic time — and this is where UTC comes in.
UTC is a time standard that sets the base for time keeping and time zones around the world. However, in the United Kingdom, GMT is still being used for civil purposes, even though not formally. The Greenwich Mean Time was created in England and adopted at the International Meridian Conference of ; then, the Earth was split into 24 time zones, with each zone being based on the Greenwich Meridian Time.
UTC time is kept using extremely precise atomic clocks that are placed in various locations around the world. Saskatchewan passed legislation declaring MST as the time to be used for the province, originally in The Act was reinterpreted in , and and was repealed in , but "stated that any official reference to time shall be deemed to be Mountain Standard Time".
Before the implementation of The Time Act in , the question of time was the responsibility of municipalities. Under The Cities Act and The Towns Act , bylaws could be passed at any time by conducting a plebiscite on the question of observed time. Voters were equally split on DST. In what government considered a compromise solution to establishing uniform time, effective April 27, , legislation was passed switching the entire province to CST until October, and MST for the winter months.
The government chose not to enforce this legislation and the result was chaos as dozens of communities in the southeast refused to change to MST in the fall of One of the conclusions of the Time Committee was that "the observance of one uniform time throughout the province all year for instance, would work except that the people of the province will never agree on whether it should be Mountain or Central Time.
After much research, consultation and deliberation, the Time Committee's recommendations were submitted to Cabinet in May and formed the basis of the legislation to be implemented. In , Sir Sanford Fleming proposed a plan to standardize time that would divide the earth into 24 standard time zones.
Each of the time zones was to be one hour different from neighbouring zones. Each zone was defined equally on either side of a standard meridian.
Meridians were placed every 15 degrees of longitude around the earth's surface. If a person were to measure the width of a time zone at a line of latitude in North America, it would average miles. This is an approximate measure since actual time zones have irregular boundaries. The difference is positive if the local time is later than UT and negative if it is earlier.
A standard meridian is located at the centre of a time zone, and 7. The degree standard meridian for MST runs approximately down the middle of the province, and 7. In February , Earl R. Milton was the only professional astronomer in Saskatchewan at that time.
Today, time zones establish order and allow national and international systems to operate, but we have maintained a fragmented time map in large countries. In the U. The Pacific Time Zone lies along the western coast of North America, reaching north from the lower 48 states of the U. The western border of the Central Time Zone begins at the northwestern edge of North Dakota and extends jaggedly down to the northwestern edge of Texas, while the eastern edge descends from Lake Michigan in Indiana down through Florida along the line of the Georgia-Alabama border.
Or let's say you are in Paris, France, Central Europe. How do you convert GMT? To convert GMT to another time zone, add or subtract the difference in hours divided by When in EST, the best time to see everyone is between 9am and 1pm for a conference call or meeting.
In GMT, normal business hours apply from 2pm to 6pm. Where is the UTC time zone? The use of UTC and GMT is based on a 24 hour clock which is equivalent to military time and is based on the 0 degree meridian, known in England as the Greenwich-Greenwich meridian.
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